Publications by authors named "A W J van"

145 Publications

Noise reduction in diffusion weighted MRI of the pancreas using an L1-regularized iterative SENSE reconstruction.

Magn Reson Imaging 2021 Nov 19. Epub 2021 Nov 19.

Department of Diagnostic and Interventional Radiology, School of Medicine, Technical University of Munich, Munich, Germany; German Cancer Consortium (DKTK), Munich partner site, Germany. Electronic address:

Objectives: To prospectively evaluate an L1 regularized iterative SENSE reconstruction (L1-R SENSE) to eliminate band-like artifacts frequently seen with parallel imaging (SENSE) at high acceleration factors in high resolution diffusion weighted magnetic resonance imaging of the pancreas.

Methods: Fourteen patients with pancreatic ductal adenocarcinoma (PDAC) underwent respiratory triggered DWI ss-EPI at a resolution of 2.5 × 2.5 × 3 mm3 with uniform undersampling in the phase encoding direction (AP axis) with an acceleration factor of 4. Data were reconstructed using the standard SENSE reconstruction routine of the vendor and an iterative SENSE reconstruction employing L1 regularization after a wavelet sparsifying transformation (L1-R SENSE). Retrospective reconstruction of the data with a lower number of averages was performed using both reconstruction methods. Two radiologists independently assessed noise artifacts, anatomical details and image quality (IQ) subjectively with a 4-point scale. Apparent diffusion coefficient (ADC) and covariance (CV) of ADC estimated from images reconstructed at a different number of averages for PDAC and the normal pancreas were assessed.

Results: L1-R SENSE resulted in higher IQ and less noise artifacts than SENSE. Anatomical details were significantly higher for SENSE in one reader. Mean ADC of PDAC and normal pancreas were significantly higher for L1-R SENSE than SENSE. L1-R SENSE revealed lower CV of ADC for normal pancreas compared to SENSE, whereas no difference was noted for PDAC.

Conclusion: Compared with traditional SENSE reconstruction, L1-R SENSE effectively reduces band-like noise and improves the robustness of the ADC estimation from acquisitions using single-shot DW-EPI of the pancreas.
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http://dx.doi.org/10.1016/j.mri.2021.11.009DOI Listing
November 2021

Individualized Functional Subnetworks Connect Human Striatum and Frontal Cortex.

Cereb Cortex 2021 Oct 28. Epub 2021 Oct 28.

Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA.

The striatum and cerebral cortex are interconnected via multiple recurrent loops that play a major role in many neuropsychiatric conditions. Primate corticostriatal connections can be precisely mapped using invasive tract-tracing. However, noninvasive human research has not mapped these connections with anatomical precision, limited in part by the practice of averaging neuroimaging data across individuals. Here we utilized highly sampled resting-state functional connectivity MRI for individual-specific precision functional mapping (PFM) of corticostriatal connections. We identified ten individual-specific subnetworks linking cortex-predominately frontal cortex-to striatum, most of which converged with nonhuman primate tract-tracing work. These included separable connections between nucleus accumbens core/shell and orbitofrontal/medial frontal gyrus; between anterior striatum and dorsomedial prefrontal cortex; between dorsal caudate and lateral prefrontal cortex; and between middle/posterior putamen and supplementary motor/primary motor cortex. Two subnetworks that did not converge with nonhuman primates were connected to cortical regions associated with human language function. Thus, precision subnetworks identify detailed, individual-specific, neurobiologically plausible corticostriatal connectivity that includes human-specific language networks.
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http://dx.doi.org/10.1093/cercor/bhab387DOI Listing
October 2021

The Ecophysiological Performance and Traits of Genera within the -like Clade (Trebouxiophyceae) under Matric and Osmotic Stress.

Microorganisms 2021 Aug 26;9(9). Epub 2021 Aug 26.

Institute for Biological Sciences, Applied Ecology and Phycology, University of Rostock, 18059 Rostock, Germany.

Changes in water balance are some of the most critical challenges that aeroterrestrial algae face. They have a wide variety of mechanisms to protect against osmotic stress, including, but not limited to, downregulating photosynthesis, the production of compatible solutes, spore and akinete formation, biofilms, as well as triggering structural cellular changes. In comparison, algae living in saline environments must cope with ionic stress, which has similar effects on the physiology as desiccation in addition to sodium and chloride ion toxicity. These environmental challenges define ecological niches for both specialist and generalist algae. One alga known to be aeroterrestrial and euryhaline is Nägeli, possessing the ability to withstand both matric and osmotic stresses, which may contribute to wide distribution worldwide. Following taxonomic revision of into seven lineages, we here examined their physiological responses to osmotic and matric stress through a salt growth challenge and desiccation experiment. The results demonstrate that innate compatible solute production capacity under salt stress and desiccation tolerance are independent of one another, and that salt tolerance is more variable than desiccation tolerance in the -like genera. Furthermore, algae within this group likely occupy similar ecological niches, with the exception of .
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http://dx.doi.org/10.3390/microorganisms9091816DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8472729PMC
August 2021

Toward a More Comprehensive Assessment of School Age Children with Hemiplegic Cerebral Palsy.

Rehabil Process Outcome 2021 27;10:11795727211010500. Epub 2021 Apr 27.

Program in Occupational Therapy, Washington University School of Medicine, St. Louis, MO, USA.

Background: Cerebral palsy (CP) is the leading cause of disability in children. While motor deficits define CP, many patients experience behavioral and cognitive deficits which limit participation. The purpose of this study was to contribute to our understanding of developmental delay and how to measure these deficits among children with CP.

Methods: Children 5 to 15 years with hemiplegic CP were recruited. Cognition and motor ability were assessed. The brain injury associated with observed motor deficits was identified. Accelerometers measured real-world bilateral upper extremity movement and caregivers completed behavioral assessments.

Results: Eleven children participated, 6 with presumed perinatal stroke. Four children scored below average intelligence quotient while other measures of cognition were within normal limits (except processing speed). Motor scores confirmed asymmetrical deficits. Approximately one third of scores indicated deficits in attention, behavior, or depression.

Conclusions: Our findings corroborate that children with CP experience challenges that are broader than motor impairment alone. Despite the variation in brain injury, all participants completed study procedures.

Implications: Our findings suggest that measuring behavior in children with CP may require a more comprehensive approach and that caregivers are amenable to using online collection tools which may assist in addressing the therapeutic needs of children with CP.
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http://dx.doi.org/10.1177/11795727211010500DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8282143PMC
April 2021

Energy crop as an environmentally sustainable reclamation option for post-mining sites: a life cycle assessment of cassava planting in Vietnam.

Environ Sci Pollut Res Int 2021 Aug 30. Epub 2021 Aug 30.

School of Environmental Science and Technology, Hanoi University of Science and Technology, No. 1 Dai Co Viet Rd., Hanoi, Vietnam.

Using post-mining areas for planting energy crops has emerged as a promising and sustainable reclamation solution due to its potential contributions to environmental protection, land restoration, and especially energy security. However, to ensure the sustainability of this reclamation solution, its environmental performance needs to be thoroughly assessed case by case. Located in Ha Thuong Commune, Dai Tu District, Thai Nguyen Province in northern Vietnam, Nui Phao is the world's largest tungsten mine. To restore post-mining sites at Nui Phao, cassava planting for ethanol production was one of the proposed measures. To support the decision-making, this study employs life cycle assessment to thoroughly evaluate the environmental performance and potential environmental benefits/costs of cassava-based reclamation system in terms of resource consumption and green house gas (GHG) emission. The results show that cassava-based reclamation might bring significant environmental benefits in terms of fossil fuel saving and GHGs reduction (i.e., reduce 50% fossil fuel consumption and 36% GHGs emission); however, it does not bring any benefit in terms of water and land resource consumption. Moreover, the results define cassava cultivation as the "hot spot" of the system, where innovations to enhance the yield and reduce water and fertilizer consumption are required to improve the environmental performance of the cassava-based reclamation system.
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http://dx.doi.org/10.1007/s11356-021-16134-0DOI Listing
August 2021
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